<template>
  <div class="type-nav" @mouseleave="mouseleaveCallback">
    <div class="container">
      <h2 class="all"
          @mouseenter="mouseenterCallback"
      >全部商品分类</h2>
      <nav class="nav" @mouseenter="mouseleaveCallback">
        <a href="###">服装城</a>
        <a href="###">美妆馆</a>
        <a href="###">尚品汇超市</a>
        <a href="###">全球购</a>
        <a href="###">闪购</a>
        <a href="###">团购</a>
        <a href="###">有趣</a>
        <a href="###">秒杀</a>
      </nav>
      <transition name="sort">
        <div class="sort" :class="{ 'display':display }"
        >
          <div class="all-sort-list2"
               v-for="c1 in baseCategoryList"
               @click="goToSearchPage"
          >
            <div class="item bo">
              <h3 @mouseenter="changeCategoryId(c1.categoryId)"
                  @mouseleave="categoryId=-1"
                  :class="{cur:c1.categoryId===categoryId}"
              >
                <a :data-category-name="c1.categoryName"
                   :data-category-id="'1-'+c1.categoryId">
                  {{ c1.categoryName }}
                </a>
              </h3>
              <div class="item-list clearfix">
                <div class="subitem"
                     v-for="c2 in c1.categoryChild"
                >
                  <dl class="fore">
                    <dt>
                      <a :data-category-id="'2-'+c2.categoryId"
                         :data-category-name="c2.categoryName"
                      >
                        {{ c2.categoryName }}
                      </a>
                    </dt>
                    <dd>
                      <em v-for="c3 in c2.categoryChild">
                        <a :data-category-id="'3-'+c3.categoryId"
                           :data-category-name="c3.categoryName"
                        >
                          {{ c3.categoryName }}
                        </a>
                      </em>
                    </dd>
                  </dl>
                </div>
              </div>
            </div>
          </div>
        </div>
      </transition>
    </div>
  </div>
</template>

<script>
import {mapState} from 'vuex'
import _ from 'lodash';

export default {
  data() {
    return {
      categoryId: -1,
      display: false
    }
  },
  methods: {
    changeCategoryId: _.throttle(function (categoryId) {
      this.categoryId = categoryId;
    }, 300),
    goToSearchPage(event) {
      let {categoryId, categoryName} = event.target.dataset;
      // 判断是否是a标签，否则不处理
      if (categoryId) {
        let level = categoryId.split('-')[0];
        let realCategoryId = categoryId.split('-')[1];
        let query = {};
        switch (level) {
          case "1":
            query.category1Id = realCategoryId
            break;
          case "2":
            query.category2Id = realCategoryId
            break;
          case "3":
            query.category3Id = realCategoryId
            break;
          default:
            return;
        }
        let location = {name: 'search'};
        query.categoryName = categoryName;
        location.query = query;
        if (this.$route.params) {
          location.params = this.$route.params;
        }
        this.$router.push(location);
      }
    },
    mouseleaveCallback() {
      if (this.$route.name === 'home') {
        return;
      }
      this.display = false;
    },
    mouseenterCallback() {
      if (this.$route.name === 'home') {
        return;
      }
      this.display = true
    }
  },
  computed: {
    ...mapState({
      baseCategoryList: (state) => state.home.baseCategoryList
    })
  },
  created() {
    if (this.$route.name === 'home') {
      this.display = true;
    }
  }
}
</script>

<style scoped lang="less">
.type-nav {
  border-bottom: 2px solid #e1251b;

  .container {
    width: 1200px;
    margin: 0 auto;
    display: flex;
    position: relative;

    .all {
      width: 210px;
      height: 45px;
      background-color: #e1251b;
      line-height: 45px;
      text-align: center;
      color: #fff;
      font-size: 14px;
      font-weight: bold;
    }

    .nav {
      a {
        height: 45px;
        margin: 0 22px;
        line-height: 45px;
        font-size: 16px;
        color: #333;
      }
    }
    .sort.display {
        transform: scaleY(1);
    }
    .sort {
      transform: scaleY(0);
      transform-origin: top;
      transition: all 0.2s;
      position: absolute;
      left: 0;
      top: 45px;
      width: 210px;
      position: absolute;
      background: #fafafa;
      z-index: 999;

      .all-sort-list2 {
        .item {
          h3 {
            line-height: 30px;
            font-size: 14px;
            font-weight: 400;
            overflow: hidden;
            padding: 0 20px;
            margin: 0;

            a {
              color: #333;
            }
          }

          .item-list {
            display: none;
            position: absolute;
            width: 734px;
            min-height: 460px;
            background: #f7f7f7;
            left: 210px;
            border: 1px solid #ddd;
            top: 0;
            z-index: 9999 !important;

            .subitem {
              float: left;
              width: 650px;
              padding: 0 4px 0 8px;

              dl {
                border-top: 1px solid #eee;
                padding: 6px 0;
                overflow: hidden;
                zoom: 1;

                &.fore {
                  border-top: 0;
                }

                dt {
                  float: left;
                  width: 54px;
                  line-height: 22px;
                  text-align: right;
                  padding: 3px 6px 0 0;
                  font-weight: 700;
                }

                dd {
                  float: left;
                  width: 415px;
                  padding: 3px 0 0;
                  overflow: hidden;

                  em {
                    float: left;
                    height: 14px;
                    line-height: 14px;
                    padding: 0 8px;
                    margin-top: 5px;
                    border-left: 1px solid #ccc;
                  }
                }
              }
            }
          }

          &:hover {
            .item-list {
              display: block;
            }
          }
        }

        .cur {
          background-color: #6badde;
        }
      }
    }

    // 过渡动画开始状态（进入状态）
    .sort-enter {
      height: 0;
    }

    // 过度动画离开状态（进入状态）
    .sort-enter-to {
      height: 461px;
    }

    // 定义动画时间、速率
    .sort-enter-active {
      transition: all 0.5s;
    }

  }
}

</style>